<!-- 图片裁剪 -->
<template>
  <el-dialog :visible.sync="dialogVisible" :width="2.5 * width" title="图片裁剪">
    <div class="cropper-content">
      <div class="cropper-box">
        <div class="cropper">
          <vue-cropper
            :autoCrop="option.autoCrop"
            :autoCropHeight="option.autoCropHeight"
            :autoCropWidth="option.autoCropWidth"
            :canMove="option.canMove"
            :canMoveBox="option.canMoveBox"
            :canScale="option.canScale"
            :centerBox="option.centerBox"
            :enlarge="option.enlarge"
            :fixed="option.fixed"
            :fixedBox="option.fixedBox"
            :fixedNumber="option.fixedNumber"
            :full="option.full"
            :height="option.height"
            :img="option.img"
            :info="option.info"
            :infoTrue="option.infoTrue"
            :maxImgSize="option.maxImgSize"
            :mode="option.mode"
            :original="option.original"
            :outputSize="option.outputSize"
            :outputType="option.outputType"
            @imgLoad="imgLoad"
            @realTime="realTime"
            ref="cropper"
          ></vue-cropper>
        </div>
        <!--底部操作工具按钮-->
        <div class="footer-btn">
          <div class="scope-btn">
            <label class="btn" for="uploads">选择图片</label>
            <input
              @change="selectImg($event)"
              accept="image/png, image/jpeg, image/gif, image/jpg"
              id="uploads"
              style="position:absolute; clip:rect(0 0 0 0);"
              type="file"
            />
            <el-button @click="changeScale(1)" icon="el-icon-zoom-in" plain size="mini" type="danger">放大</el-button>
            <el-button @click="changeScale(-1)" icon="el-icon-zoom-out" plain size="mini" type="danger">缩小</el-button>
            <el-button @click="rotateLeft" plain size="mini" type="danger">↺ 左旋转</el-button>
            <el-button @click="rotateRight" plain size="mini" type="danger">↻ 右旋转</el-button>
          </div>
        </div>
      </div>
      <!--预览效果图-->
      <div class="show-preview">
        <div :style="previews.div" class="preview">
          <img :src="previews.url" :style="previews.img" />
        </div>
      </div>
    </div>
    <!-- 底部按钮 -->
    <div class="dialog-footer" slot="footer">
      <el-button @click="closeDialog">取 消</el-button>
      <el-button @click="uploadImg" type="primary">确 定</el-button>
    </div>
  </el-dialog>
</template>

<script>
import { VueCropper } from 'vue-cropper'
export default {
  name: 'CropperImage',
  components: {
    VueCropper
  },
  props: {
    name: {
      type: String,
      default: 'cropperImage'
    },
    width: {
      type: Number,
      default: 300
    },
    height: {
      type: Number,
      default: 300
    }
  },
  data() {
    return {
      dialogVisible: false,
      previews: {},
      option: {
        img: '', // 裁剪图片的地址
        outputSize: 1, // 裁剪生成图片的质量(可选0.1 - 1)
        outputType: 'jpeg', // 裁剪生成图片的格式（jpeg || png || webp）
        info: true, // 图片大小信息
        canScale: true, // 图片是否允许滚轮缩放
        autoCrop: true, // 是否默认生成截图框
        autoCropWidth: this.width, // 默认生成截图框宽度
        autoCropHeight: this.height, // 默认生成截图框高度
        fixed: true, // 是否开启截图框宽高固定比例
        fixedNumber: [this.width / this.height, 1], // 截图框的宽高比例
        full: false, // false按原比例裁切图片，不失真
        fixedBox: true, // 固定截图框大小，不允许改变
        canMove: false, // 上传图片是否可以移动
        canMoveBox: true, // 截图框能否拖动
        original: false, // 上传图片按照原始比例渲染
        centerBox: false, // 截图框是否被限制在图片里面
        height: true, // 是否按照设备的dpr 输出等比例图片
        infoTrue: false, // true为展示真实输出图片宽高，false展示看到的截图框宽高
        maxImgSize: 3000, // 限制图片最大宽度和高度
        enlarge: 1, // 图片根据截图框输出比例倍数
        mode: `${this.width}px ${this.height}px` // 图片默认渲染方式
      }
    }
  },
  methods: {
    // 初始化函数
    imgLoad(msg) {
      console.log('工具初始化函数=====' + msg)
    },
    // 图片缩放
    changeScale(num) {
      num = num || 1
      this.$refs.cropper.changeScale(num)
    },
    // 向左旋转
    rotateLeft() {
      this.$refs.cropper.rotateLeft()
    },
    // 向右旋转
    rotateRight() {
      this.$refs.cropper.rotateRight()
    },
    // 实时预览函数
    realTime(data) {
      this.previews = data
    },
    // 选择图片
    selectImg(e) {
      const file = e.target.files[0]
      if (!/\.(jpg|jpeg|png|JPG|PNG)$/.test(e.target.value)) {
        this.$message({
          message: '图片类型要求：jpeg、jpg、png',
          type: 'error'
        })
        return false
      }
      // 转化为blob
      const reader = new FileReader()
      reader.onload = (e) => {
        let data
        if (typeof e.target.result === 'object') {
          data = window.URL.createObjectURL(new Blob([e.target.result]))
        } else {
          data = e.target.result
        }
        this.option.img = data
      }
      // 转化为base64
      reader.readAsDataURL(file)
    },
    closeDialog() {
      this.dialogVisible = false
    },
    openDialog() {
      this.dialogVisible = true
    },
    // 上传图片
    uploadImg(type) {
      if (type === 'blob') {
        // 获取截图的blob数据
        this.$refs.cropper.getCropBlob(async (data) => {
          this.$api.upload({ files: data }).then(res => {
            this.$emit('input', res.data[0])
          }).catch(err => {
            console.log(err)
            this.$message({
              message: '文件服务异常',
              type: 'error'
            })
          })
        })
      }
    }
  }
}
</script>

<style scoped lang="scss">
.cropper-content {
  position: relative;
  z-index: 3000;
  display: flex;
  justify-content: flex-end;

  .cropper-box {
    flex: 1;
    width: 100%;
    .cropper {
      width: auto;
      height: 300px;
    }
  }

  .show-preview {
    min-height: 300px;
    margin-top: 10px;
    flex: 1;
    -webkit-flex: 1;
    display: flex;
    justify-content: center;
    .preview {
      overflow: hidden;
      border: 1px solid #67c23a;
      background: #cccccc;
    }
  }
}
.footer-btn {
  margin-top: 30px;
  display: flex;
  justify-content: flex-end;
  .scope-btn {
    display: flex;
    justify-content: space-between;
    padding-right: 10px;
  }
  .upload-btn {
    flex: 1;
    -webkit-flex: 1;
    display: flex;
    justify-content: center;
  }
  .btn {
    outline: none;
    display: inline-block;
    line-height: 1;
    white-space: nowrap;
    cursor: pointer;
    text-align: center;
    box-sizing: border-box;
    outline: 0;
    transition: 0.1s;
    font-weight: 500;
    padding: 8px 15px;
    font-size: 12px;
    border-radius: 3px;
    color: #fff;
    background-color: #409eff;
    border-color: #409eff;
    margin-right: 10px;
  }
}
</style>
